Displays for projecting an image on a screen thereof are known. Rear projections applied to a monitor for a home theater, a large screen television, or the like are known as such the display.
A rear projection having a microlens substrate with a plurality of microlenses (i.e., microlens substrate) is known as such a rear projection. The rear projection having the microlens substrate has an advantage to obtain fine view angle characteristics in both vertical and lateral directions of the screen by means of light reflection of the microlenses.
Further, in the devices with the microlens substrate, a black matrix (a shield layer) is normally formed on the microlens substrate in order to improve the contrast and to prevent a lowering of visibility, uneven display, blur of an image, or the like.
Formation of the black matrix is normally carried out by means of a wet etching process using a resist. Namely, a thin film is formed on a surface opposite to the surface of the microlens substrate on which the microlenses are provided by means of Chemical Vapor Deposition method (CVD method), and a resist layer with a pattern of openings (i.e., a portion other than the portion on which the black matrix is formed in the thin film) is formed on the thin film. Then, the openings are formed on the thin film by the wet etching process, and then the black matrix is formed by removing the resist layer.
However, such a method has a defect of less productivity due to many processes (or many steps). Further, since alignment is indispensable for such a method, it is difficult to apply the method to a relatively large-sized microlens substrate as used for a rear projection. A plurality of relatively small-sized microlens substrates may be used in combination for a rear projection or the like. In this case, there is a problem that seams of bonding of the microlens substrates appear on a projected image.